For some weapons, such as grenade launching machine guns which fire relatively slow rounds, it is necessary to elevate the weapon by a significant angle above the line of sight to the target (e.g., by an angle greater than half the field of view of the gun sight) in order to reach the target with the grenade round. Such weapons are often used in conjunction with a gun sight that is coupled with a display that presents an image of a down range area that includes the target. An aiming reticle is often displayed on the display, the position of which is calculated by a ballistic algorithm, to assist the operator in aiming the weapon and engaging a target down range.
Modern gun sights have high levels of magnification that permit precise aiming of the weapon at long ranges. Such gun sights provide a field of view of only a few degrees. When a targeting solution is determined that requires superelevation, the gun sight may be elevated together with the weapon and the target will very likely move off of the display when the required superelevation exceeds the field of view. This loss of visual contact with the target during superelevation is undesirable.
One solution to this problem was described in U.S. Pat. No. 6,499,382 issued to Lougheed et al. Lougheed describes a grenade machine gun or other weapon that employs superelevation of the barrel and an aiming system. The aiming system is mounted to both the weapon and the weapon's support or base. The aiming system is configured to alternatively lock to either the weapon or to the weapon's support. When locked to the weapon, the aiming system is free to rotate in elevation and azimuth in unison with the weapon. When locked to the weapon support, the aiming system is restrained from elevation and thus the weapon can be superelevated while the aiming system remains oriented at a static elevation angle. In this manner, the weapon can be superelevated yet still allow an operator to maintain visual contact with the target on the display.
While this solution is adequate, there is room for improvement. For example, Lougheed's aiming system is large and has substantial mass. Additionally, systems constructed in accordance with Lougheed's disclosure have historically been very expensive. Also, in some circumstances, it may not be sufficient or desirable to lock the aiming system into a static elevation angle with respect to the weapon support. For example, the terrain may be sandy or muddy or otherwise unstable. On such terrain, superelevation of the weapon or other circumstances may cause the weapon support to shift. This, in turn, would cause an unintended deviation of the aiming system and possibly a loss of line of sight to the target. Furthermore, by having the gun sight attach to the weapon mount, the gun sight is less adaptable for use with different weapons. A less massive, less expensive gun sight that is not statically locked to the weapon's base during superelevation and that provides greater adaptability for use with multiple weapons is desired. Furthermore, other desirable features and characteristics of the present disclosure will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and the foregoing technical field and background.